998895509 has 2 divisors, whose sum is σ = 998895510. Its totient is φ = 998895508.

The previous prime is 998895487. The next prime is 998895529. The reversal of 998895509 is 905598899.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 870073009 + 128822500 = 29497^2 + 11350^2 .

It is an emirp because it is prime and its reverse (905598899) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 998895509 - 2²⁰ = 997846933 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (998895529) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499447754 + 499447755.

It is an arithmetic number, because the mean of its divisors is an integer number (499447755).

Almost surely, 2^998895509 is an apocalyptic number.

It is an amenable number.

998895509 is a deficient number, since it is larger than the sum of its proper divisors (1).

998895509 is an equidigital number, since it uses as much as digits as its factorization.

998895509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10497600, while the sum is 62.

The square root of 998895509 is about 31605.3082408636. The cubic root of 998895509 is about 999.6317007056.

The spelling of 998895509 in words is "nine hundred ninety-eight million, eight hundred ninety-five thousand, five hundred nine".